Fabrication of magnetic cerium-organic framework-activated carbon composite for charged dye removal from aqueous solutions

Magnetic MOF-808 as a novel adsorbent for toxic metal removal from aqueous solutions

“…The solid product (Zr-MOF) was dried at 50 °C for 24 h. Fe 3 O 4 nanoparticles were synthesized using the co-precipitation method reported in our previously published work. 16 The synthesis of the magnetic Zr-MOF was carried out by a simple mixing and stirring process. Firstly, 1.0 g of Zr-MOF in 50 mL of water and 0.5 g of Fe 3 O 4 in 50 mL of water were separately sonicated.…”

“…The band at 675 cm À1 was due to the A 1g mode for the symmetric stretching of the oxygen atoms in the tetrahedral FeO 4 groups. 16 The spectral features of Fe 3 O 4 and Zr-MOF were observed in the Raman spectrum of the Zr-MOF@Fe 3 O 4 composite.…”

“…29 The TGA prole of Zr-MOF@Fe 3 O 4 showed a signicantly low mass loss in the entire temperature range compared to the pristine Zr-MOF, which conrmed that the composite was more stable than the Zr-MOF. 16 The VSM curves of Fe 3 O 4 and Zr-MOF@Fe 3 O 4 at 300 K are shown in Fig. 2e.…”

“…It is well known that the intra-particle diffusion process consists of three steps: mass transfer, adsorption, and diffusion. 16,44 The data were tted in two regions, which were regarded as two adsorption processes (Fig. 6d).…”

“…† The correlation coefficient (R 2 ) of the Freundlich model (0.99) was higher than those of the Langmuir (0.97), D-R (0.95), and Temkin (0.88) models, indicating that the adsorption process was multilayer adsorption. 16,41 This suggested that the physicochemical forces over the MOF surface play the primary role in the Hg(II) adsorption. The separation factor (R L ) computed from the Langmuir model remained between 0 and 1, suggesting a favourable Hg(II) adsorption process over Zr-MOF@Fe 3 O 4 .…”